Stringing pianos



(No Model) L. G.-TH.ERRIEN.

STRING-1N6: PIANOS.

No. 288,279. Patented Nov. 13, 1883. 5: 1 H 7 n FL- 5' I I! l 1 W b1 2 5s as.

" UNITED STATES PATENT OFFICE.

LOUIS O. TIIEERIEN, OF MONTREAL, QUEBEC, CANADA, ASSIGNOR, BY DI- uEOTAND MESNE ASSIGNMENTS, OF SEVENTEEN TlVENTY-FOURTHS TO AUGUSTIN LAVALLEEAND ADOLPHE OUIMET, OF SAME PLACE, AND TREFFLE GAROEAU, OF BOSTON,MASSACHUSETTS.

STRINGING PIANOS.

SPECIFICATIQN forming part of Letters Patent No. 288,279, dated November13, 1883,

Application filed May 18,1883.

To all whom it may concern.-

Be it known that 1, Louis 0. THERRIEN, of Montreal, in the Province ofQuebec and the Dominion of Canada, have invented a new and useful Devicefor Stringing Pianos, of which the following is a specification.

My invention relates to improvements in devices for stringing pianos, inwhich levers are employed for maintaining the desired strain.

Hcretofore in stringing pianos by means of levers the lon arm of thelever has been secured by means of a spring. In such arrangement it isevident that the tension of the spring, and consequently the strain onthe string, must I 5 vary, since the slight movement of the short arm ofthe lever, caused by the expansion and contraction of the string, causesa great movement of the long arm, thereby bringing a greater or lessstrain on the spring.

The object of any invention is to provide a device for keeping thestrings of apiano-forte under a constant and unvarying tension, so thatwhen a string is once adjusted to the proper tension-say to produce acertain musical 2 5 note-it will continue to give that note and no otherwith out further adjustment or tuning, (as it is commonly called,)regardless of the use, abuse, or changes of temperature to which it maybe subjected.

My invention is obviously applicable to any line or cord subjected tostrain.

My invention consists, mainly, in the combination,with a string securedat one end, of a weight connected to the string by a system of 3 5levers proportioned to cause the weight to produce the desired tension,as hereinafter fullyset forth.

In the accompanying drawings,whieh illustrate so much of a piano stringframe and 40 sounding-board as is deemed necessary to show my improveddevice for straining the strings as arranged in the best way now knownto me,

Figure l. is a longitudinal section, showing a string of an uprightpiano with the straining 5 device attached. Fig. 2 is a front view, and

Fig. 3 is a rear view of a portion of the stringframe.

The strings A are secured at one end in any (N0 model.)

suitable way. In this instance .I have shown them attached towrest-pins,which are prefero ably used, as by means of/them the stringsmay be brought nearly to tune, and thereby reduce any subsequentadjustment of the levers to the minimum. The strings A are secured attheir other ends to the short arms of levers l3, hav- 5 ing theirfulcrums' atb,and their long arms connected to the long arms of otherlovers, 1%, having their fulcrums at i).

To the long arm of the levers B are attached weights O, which, by meansof the compound leverage above mentioned, give the desired tension tothe strings. The weights 0 are made of flat plates and quite lightsayabout one pound eachso as not to obj eetionably in crease the weight ofthe instrument. Each plate 0 has small screw-threaded rods or wires 0secured to its lower end. These rods 0 pass through perforations in aplate or board, 0, and are provided with nuts 0' below the board 0'.These nuts ciwhen the strings are properly 7o tuned, are screwed near totheboard 0, but not touching it, so as to leave sufficient space for themovement of the plate 0 incident to the contraction and expansion of thestrings. By means of these rods cand the nuts 0, the plates O areprevented from becoming displaced or unduly moving when a piano isturned on end or otherwise in transportation. As above mentioned, thestrings are very nearly tuned by putting on the weights, and if not inperfect tune they can be made so by means of the screws 1) in the endsof the levers B, adapted to turn but prevented from moving endwise, andbearing on the knife-edges of the fulcrums b of these levers, so that byturning these 8 5 screws their threads engage with the knifeedges,whereby the position of these levers in relation to their fulcrunis canbe delicately and accurately adjusted, so as to increase or diminish thestrain on the string to the slight o extent required.

It is evident that when the strings and weights are once properlyadjusted they will remain so indefinitely, and the usual frequenttunings heretofore required in pianofortes 9 5 will not nowbe necessary.I have held pieces of red-hot iron in proximity to strings tuned 2. Thecombination, in a piano-forte, of the 10 inthis way, and Ihave alsokinked such strings string, the compound levers, the weight, the with apair of nippers without varying their screw, and the fulcrum having itsedge adapttones in the slightest. ed'to engage with the thread of thescrew, sub- I claim as my invention stantially as and for the purposeset forth. 1. In'a piano-forte,'the combination, with a I LOUIS G.THERRIEN.

I string, A, of the compound levers B and B I WVitnesses:

and weight C, arranged substantially as de- G. B. MAYNADIER, scribed,and for the purpose set forth. R. SNOW.

